I did not know that MTH had designed the Alco PA's with a different drive. I have many of their engines and the motors are in the trucks. I was shocked to learn today that the PA has all wheel drive with vertical motors. I never bought these engines as I went out of work when they were originally released. I'll have to look further at how strong a puller they are vs. the dash 8s.
All I got my hands on was a slave unit. I need to adapt it to run with a F series or just install full PS inside to run alone. I'd have to bet the gearing would be different? I now wish that I had gotten a set of these!